The Thwaites glacier is one of the most rapidly changing in Antarctica. It’s been the focus of considerable attention in recent weeks, after scientists suggested that this sector of the huge West Antarctic Ice Sheet was already on route towards collapse due to warming ocean temperatures. A major collapse of this part of the ice sheet could have dire consequences worldwide, with a global sea level rise of potentially up to 1m. Some models suggest this could take place comparatively rapidly, within a few centuries. But hidden beneath the kilometres of ice in this rapidly changing part of the...